The former Morgan Stanley co-president, who was publicly ousted from the firm in 2007 amid the financial meltdown, is no stranger to corporate warfare.

But this time the battle is personal: Cruz is going through a divorce from her longtime partner and fellow financier, Credit Suisse honcho Ernesto Cruz, while she also tries to make her return to high finance.

The breakup of the Wall Street power couple caps a tumultuous year for Cruz, 57, who just five months ago was forced to shut down her $200 million hedge fund Voras Capital. The macro fund, which tried to profit from broad economic trends, lost 8 percent last year, according to Bloomberg News.

The personal and professional setbacks come as Cruz — the one-time heir apparent to former Morgan Stanley CEO John Mack — looks for her next job, possibly in the private-equity realm.

Sources say she has reconciled with her former boss Mack, who helped fuel her rise within their firm before their falling out. He has been helping his one-time protégée in her efforts to land at a buyout firm such as KKR.

Mack also has been a shoulder for Cruz to lean on as she copes with the split, according to sources familiar with the situation.

Sources said that the couple has been married for more than three decades. They have three children, with the youngest still in high school.

Cruz, a Greek immigrant (née Papadimitriou) who arrived in America when she was a teenager and methodically climbed the Wall Street ladder, was blind-sided by the divorce, sources said.

“She never saw this coming,” said one Wall Street insider.

Added another source: “Ernesto was her rock.”

A spokeswoman for Zoe Cruz declined to comment.

The couple stuck together in the wake of her embarrassing ouster from Morgan Stanley in 2007, after the firm suffered a $9 billion loss that fell at her feet.

Once hailed as one of the most powerful women on Wall Street, Cruz was well on her way to succeeding Mack until a trading blow-up from soured mortgages in an area that she oversaw forced him to level the ax.

Zoe Cruz and her husband in many ways embodied the American dream. Both are from immigrant families whose talent, ambition and hard work allowed them to push into Wall Street’s clubby elite circles.

A Nicaraguan immigrant, Ernesto is a 27-year veteran of Credit Suisse and the current head of the firm’s global equity capital markets.

Sources say that Ernesto has moved out of their Manhattan residence.

He was once reprimanded by his superiors in the mid-2000s for frolicking in a hotel pool in Midtown after a company Christmas gala with a group of female assistants, according to sources familiar with the situation.

He couldn’t be reached for comment, while his attorney didn’t return calls and messages for comment.